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311.
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Stéphane De Mita Anne‐Céline Thuillet Laurène Gay Nourollah Ahmadi Stéphanie Manel Joëlle Ronfort Yves Vigouroux 《Molecular ecology》2013,22(5):1383-1399
Thanks to genome‐scale diversity data, present‐day studies can provide a detailed view of how natural and cultivated species adapt to their environment and particularly to environmental gradients. However, due to their sensitivity, up‐to‐date studies might be more sensitive to undocumented demographic effects such as the pattern of migration and the reproduction regime. In this study, we provide guidelines for the use of popular or recently developed statistical methods to detect footprints of selection. We simulated 100 populations along a selective gradient and explored different migration models, sampling schemes and rates of self‐fertilization. We investigated the power and robustness of eight methods to detect loci potentially under selection: three designed to detect genotype–environment correlations and five designed to detect adaptive differentiation (based on FST or similar measures). We show that genotype–environment correlation methods have substantially more power to detect selection than differentiation‐based methods but that they generally suffer from high rates of false positives. This effect is exacerbated whenever allele frequencies are correlated, either between populations or within populations. Our results suggest that, when the underlying genetic structure of the data is unknown, a number of robust methods are preferable. Moreover, in the simulated scenario we used, sampling many populations led to better results than sampling many individuals per population. Finally, care should be taken when using methods to identify genotype–environment correlations without correcting for allele frequency autocorrelation because of the risk of spurious signals due to allele frequency correlations between populations. 相似文献
313.
314.
Rozhin Ahmadi 《Archives Of Phytopathology And Plant Protection》2013,46(12):1415-1425
Greenbug, Schizaphis graminum (Rondani), is one of the injurious aphids of cereals in various regions of the world. This study has measured the life table parameters of the greenbug on six barley genotypes at 25 ± 2 °C, 55 ± 10% RH and 16:8 L:D in greenhouse. According to the results, significant differences were not observed for aphids’ developmental times among the genotypes. Also, the nymphs underwent no mortality on any of the tested genotypes. The longevity of the aphids was obtained from 23.7 to 35.9 days. The least mean number of offsprings was on Raihan cultivar and the highest on line13 (Legia/CWB117-5-9-5). R0 value was significantly higher on line 20 (Mall-4-3094-2//Alpha/Cum/3/Victoria/ICB01-1368-0AP) and line 13 than on the Raihan cultivar. However, the rm and λ values were significantly higher on line 44 (Sls/Bda//Sararood-1) than on Raihan cultivar. T (mean generation time) and DT (doubling time) values of the Raihan cultivar were longer than the other genotypes. Results of this research indicated that among the tested genotypes, the Raihan cultivar is the most unsuitable host for greenbug aphid and lead to the decrease of greenbug population growth. 相似文献
315.
Milad Ashrafizadeh Hojjat Samareh Fekri Zahra Ahmadi Tahereh Farkhondeh Saeed Samarghandian 《Journal of cellular biochemistry》2020,121(2):1575-1585
Since the beginning of the 21st century, studies have focused on developing drugs from naturally occurring compounds. Berberine (Brb) as a plant-derived compound is of interest. It is an isoquinone alkaloid which is derived from Berberis aristata, Berberis aquifolium and Berberis vulgaris. This plant-derived compound has a variety of pharmacological effects such as antioxidant, anti-inflammatory, antidiabetic, antidiarrheal, antitumor, antimicrobial, and anti-inflammatory. Various studies have demonstrated the therapeutic and biological activities of Brb, but there is a lack of a precise review to manifest the signaling pathway of action of Brb. The nuclear factor erythroid 2-related factor 2 (Nrf2) is a highly conserved pathway which mainly involves in preservation of redox balance. At the present review, we describe the therapeutic and biological activities of Brb as well as the relevant mechanisms specially focused on the Nrf2 signaling pathway. 相似文献
316.
Zahra Alimanesh Zeynab Alimanesh Fatemeh Davari Saeedeh Shadmehri Mozhgan Ahmadi Seyed Ali Hosseini Sepideh Dolati Alemeh Hariri Far 《Molecular & cellular biomechanics : MCB》2020,17(4):155-163
Diabetes mellitus (DM) disease can affect process of apoptosis by
increasing oxidative stress, nevertheless exercise and crocin can improve apoptosis; therefore present study aimed to investigate the effect of continued training
with crocin on apoptosis markers in liver tissue of diabetic rats. In this experimental study 32 diabetic rats based on fasting glucose divided into four groups of
eight rats including: 1) sham, 2) training, 3) crocin, and 4) training with crocin
also for investigate the effect of DM induction on apoptosis markers, eight healthy
rats assigned in healthy control group. During eight weeks groups 2 and 4 ran
60 minutes on treadmill with intensity of 50–55% maximum speed for three sessions per week and groups 3 and 4 received 25 mg/kg/day crocin peritoneally.
Shapiro–Wilk, one-way ANOVA with Tukey’s post-hot tests were used for statistical analysis of data (P ≤ 0.05). DM induction significantly increased Bcl-2 as
well as decreased Bax and P52 (P ≤ 0.05) nevertheless training and training with
crocin significantly decreased Bcl-2 and increased Bax and P53 (P ≤ 0.05); crocin
significantly decreased Bcl-2 and increased P53 (P ≤ 0.05) and training with crocin had higher effect on increase of Bax and P53 compare to training (P ≤ 0.05)
also increase of Bax compare to crocin. Although training and crocin alone can
improve apoptotic markers in diabetic rats, nevertheless training simultaneously
with crocin have better effects than training alone. 相似文献
317.
318.
A theoretical study of a series of five glucose based glycolipid crown ethers and their complexes with Na+ and K+ was performed using the density functional theory with B3LYP/6-31?G* to obtain the optimized geometrical structures and electronic properties. The local nucleophilicity of the five molecules was investigated using Fukui function, while the global nucleophilicity was calculated from the ionization potential and electron affinity. The structures and coordination of the complexes were studied to identify the best match of the glycolipid crown ethers with cations. In general, it was found that the oxygen atoms pairs O2 and O3 (or O4 and O6) on the sugar ring are constrained from moving toward the cation, which results in a weaker O-cation coordination strength for the oxygen pair compared to the other oxygen atoms in the crown ether ring. The thermodynamic properties of the binding of the complexes and the exchange reaction in gas phase were evaluated. The cation selectivity pattern among the five molecules was in good agreement with the experiment. 相似文献
319.
320.
Paul J. Zak Robert Kurzban Sheila Ahmadi Ronald S. Swerdloff Jang Park Levan Efremidze Karen Redwine Karla Morgan William Matzner 《PloS one》2009,4(12)
How do human beings decide when to be selfish or selfless? In this study, we gave testosterone to 25 men to establish its impact on prosocial behaviors in a double-blind within-subjects design. We also confirmed participants'' testosterone levels before and after treatment through blood draws. Using the Ultimatum Game from behavioral economics, we find that men with artificially raised T, compared to themselves on placebo, were 27% less generous towards strangers with money they controlled (95% CI placebo: (1.70, 2.72); 95% CI T: (.98, 2.30)). This effect scales with a man''s level of total-, free-, and dihydro-testosterone (DHT). Men in the lowest decile of DHT were 560% more generous than men in the highest decile of DHT. We also found that men with elevated testosterone were more likely to use their own money punish those who were ungenerous toward them. Our results continue to hold after controlling for altruism. We conclude that elevated testosterone causes men to behave antisocially. 相似文献